The castle of Kudrynytsia (ukr.: Кудринці) is one of the most picturesque and at the same time least known Podolia strongholds. It is located in the Borszczov region of the Ternopil region in Ukraine. The town was founded under the Magdeburg Law in 1518, on the initiative of the Herburt family. The newly formed urban organism had no fortifications and, due to its location, was exposed to Tartar incursions. The owners therefore had to think about erecting a castle nearby, combining the function of their defensive headquarters and a refuge for the local population in case of attack. It is assumed that this work was carried out by the Ruthenian Voivode Mikolaj Herburt of Dziedziłów (†1602).

The castle, built of stone and originally plastered, is located to the northeast of the town, on a site of considerable defensive value. The building occupied the top of a narrow rocky promontory, between the Zbrucz River and a deep ravine through which a small watercourse flowed. Access from the west was defended by a deep moat carved into the rock. The castle was founded on the plan of an irregular quadrangle, narrowing towards the Zbrucz. The entrance was through a quadrilateral tower in the north-western corner of the walls, to which a small residential room for the gate-keeper and guards was attached. The western defence wall was equipped with rifles for small arms, placed on three levels. It was flanked by a hexagonal fire tower with key shoots located in the south-west corner of the castle. It controlled both the entrance to the fortress and the aforementioned ravine. The last of the castle towers, now almost completely ruined, and originally probably pentagonal, was placed in the south-east corner. This defence work flanked the southern perimeter wall and covered the road from the town to the castle with gunfire. It also protected a small vaulted gatehouse leading towards the river. On the Zbruch side, where the slopes of the castle promontory slope steeply down almost to the water, only the curtain walls provided defence - it was apparently considered that the threat of attack in this direction would be small. The main castle house was also situated on this safest side, i.e. the seat of the owners for the duration of their stay in Kudryniec. In view of the considerable destruction of the castle walls, little can be said about the architecture of this building. It adjoined the northern defence wall, was built on a quadrilateral plan and, according to Aleksandr Czołowski, had three localities in the ground floor. Between this building and the eastern curtain there was another building, probably with an auxiliary function, also divided in the ground floor into three rooms. Czołowski also saw a funnel-shaped hollow next to the hexagonal tower, which may have been a trace of the castle well. Nothing is known about the location of the stronghold's outbuildings; they were probably located in the bailey, on the west side.

Both the history of the building and the transformation of its architecture are very poorly understood and require further research. During the war with the Ottoman Empire in 1672-1676, the castle, like most of the fortresses in Podolia, fell into Turkish hands. At that time, the defensive qualities of the castle were already so poor that the Turks' seizure did not entail major damage. From then on, the structure was manned by a Turkish garrison, but its strategic importance was minor. The Kudryniec "castrum" returned to the Polish-Lithuanian Commonwealth as a result of the Podolia campaign of Andrzej Potocki, castellan and voivode of Kraków. The castle then began to play a more important military role, as a base for military actions against Kamieniec Podolski, which remained in Ottoman hands. After the Peace of Karlovitsa in 1699. Kudryńce lost its strategic importance. In the 18th century, the castle remained in the hands of the Humiecki family of the Junosza coat of arms. Although it was not the main seat of this family, it was probably kept in good condition. It is not known whether the Humiecki family carried out any construction or modernisation works on the castle, apart from the current necessary repairs. If so, they were not very extensive, as the stronghold has retained its austere, primarily military character to this day (already Czołowski noted that there are "no traces of inscriptions or ornaments" on the castle). In the mid-19th century, the building was abandoned and began to fall into ruin. This process accelerated at the end of the 19th century, when Majer Bartfeld was the owner of the ruins. The planned demolition of the castle ruins for building material began at that time. The rest of the destruction was done by atmospheric factors and erosion of the unprotected castle walls A few years before Aleksander Czolowski's visit, most of the walls of the south-eastern tower had collapsed. The castle courtyard was covered with rubble "up to the height of almost the first floor". When the castle ruins were inventoried in 1937, most of the northern curtain, which had collapsed into the Zbruch as a result of a landslide on the castle promontory, no longer existed.

Nowadays, what remains of the castle are the relics of the perimeter walls, the gate tower and the south-western hexagonal tower. Two walls on the south-eastern side have survived from the south tower. The internal buildings of the castle are completely unreadable. The monument is subject to further erosion and is in need of preservation work.

The castle in Kudryniec, although small and with an uncomplicated spatial layout, nevertheless deserves attention. It is remarkable that its architecture has not undergone any major changes over the centuries. This gives us an excellent insight into the solutions of the fortification art of the 16th century. The castle appears to have been built primarily as a fortress and refugium for the population, while its residential role was secondary. This may have been influenced by the person of the initiator of the castle's construction, Nicholas Herburt. For many years, he served as a rittmeister in the army of the common defence, and was familiar with the arcana of the art of war. At the same time, he repeatedly showed interest in the defence of the south-eastern periphery of the state, so he must have appreciated the importance of fixed points of resistance. Undoubtedly, the very location of the castle, which at the same time provided an opportunity to observe the surroundings, was of considerable defensive value. This location of the building probably determined the final shape of the fortifications to a considerable extent. The castle, especially its western front, presents features of a bastion system (high and massed fire towers flanking each other). This system, although already obsolete by the end of the 16th century, was commonly used in castles in Podolia (e.g. Krzywcze, Skala Podolska). In Kudrynytsia, however, the bastion defence system was modified in the spirit of the old Italian school of fortification - for a pentagonal "puntone" was placed on the south-eastern side, ruling over the access road to the castle. This shows that the builders (or perhaps the owner) of the castle were looking for new, more effective defensive works, which is characteristic of most of the defences erected in the 2nd half of the 16th century.